134 PICTURESQUE SKETCHES 



a continent or an island, or a succession of islands, and 

 such like queries, are not at present capable of being 

 answered. Neither do we learn much more definitely 

 the general character of the animals and vegetables 

 that were indigenous. A few fragments of fossil 

 wood found in England are evidence of the fact that 

 the land was partly clothed with large pine-like trees ; 

 and a few casts of shells show that its shores were 

 peopled with some species of mollusca. Elsewhere, 

 when the conditions have been more favourable for the 

 deposition and preservation of organic remains, as in 

 some districts on the Continent, we find still a com- 

 parative poverty. Plants, indeed, abound, and ex- 

 hibit characters unlike those of the coal period ; a bed 

 of limestone (the Muschelkalk) contains numerous 

 shells, and the remains of fishes and reptiles ; but, 

 on the whole, the general features remain obscure. 

 It would almost seem that at this time, and in most 

 districts which we can examine, there had been a 

 destruction of the previous species, and that a suffi- 

 cient time had not yet elapsed for the newly in- 

 troduced groups to spread over the earth and seas. 

 However this may be, we cannot doubt the fact 

 that there had been great and sudden changes, 

 whether these were or were not connected with 

 an interruption of the order of succession, and with 

 the termination of one geological period, and the 

 commencement of a second. The new red sandstone 

 affords material for a distinct chapter in the earth's 

 history, and though it is certainly a chapter containing 

 less detail and fewer points for minute description 

 than many others, it does not fail to suggest impor- 

 tant generalisations. 



